The hardest part of tree-sitting at the University of California-Santa Cruz isn’t the cold, the rain, or the fierce winds that rattle your perch.

What’s tough is what’s happening on the ground: Threatened suspensions. Arrests. And the challenge of communicating – from 70 feet up, while wearing a ski maskto hide your identity – to students who are largely unaware of your mission to squelch campus growth.

It’s no sylvan sanctuary. Protesters awake to the roar of buses climbing Science Hill, carrying students to overcrowded classrooms and too few labs – the soundtrack of a campus bursting at the seams.

“It’s noisy,” said a protester who would identify himself only as “Owl,” speaking from a small redwood in a parking lot that is the future site of a new Biomedical Sciences Building, part of the university’s overall expansion plan.

“It feels much more like a forest at night,” he said.

The protest represents the latest collision of eco-idealism with the ambitions of a major research university, which hopes to add 4,500 students and 3.8 million square feet of new construction by 2020.

Like other UCs, the university is mandated to provide education for California’s skyrocketing number of eligible high school graduates. But elected officials in the quirky, left-leaning city say such growth will tax resources and forever change their tiny Utopia by the Sea.

Like their treetop brethren at UC-Berkeley, who for a year have been sitting in the way of a $125 million sports training center, the UC-Santa Cruz protesters have put down roots.

It has been 92 days since they hoisted up platforms in the dark and climbed out onto limbs, wrapped in layers of wool, fleece and what they assert is their right to free speech. The university says they are not students.

Early on in the campaign, incidents of graffiti, vandalism and false fire alarms angered some would-be supporters.

But a recent crackdown by school officials may sway popular opinion again. Seven protesters face criminal charges for disobeying police officers. As many as 30 face civil sanctions – including a popular professor who was sued by the university after delivering warm Miso soup.

A 19-year-old freshman who did not climb a tree but supported the demonstrators has been threatened with a two-month suspension.

But most students on this protest-proud campus seem largely unmindful, scurrying to class past signs reading “Pedestrian Warning!”

“The vast majority of people have no idea why they’re in the trees,” said campus lecturer and longtime city Councilman Mike Rotkin. “They haven’t been successful in getting their message out.”

Meanwhile, representatives of the university, city of Santa Cruz and the county are in mediation, attempting to resolve their differences over three impacts identified in the long-range plan: housing, water and transportation.

Jennifer Charles, a spokeswoman for the sitters, says that construction of the Biomedical Sciences Building is the first step in a plan that imperils both the quality of the education and the environment. “We’re here until the university changes its plans,” Charles said.

Each sturdy treehouse is equipped with a cargo line, so that ground crews can send up supplies. Sitters wear harnesses to prevent a fall. They urinate in bottles and defecate in buckets, using a hand sanitizer to keep clean. Every several days, the sitters change shifts, descending and ascending in darkness, to escape notice.

High winds rattle branches and catch the tarps like sails. During heavy rains, the sitters add layers of clothing.

A social crowd, protesters visit by traversing to each other’s trees. They’ve been serenaded by the Raging Grannies and fed warm squash and rice casseroles.

“I’ve been pretty busy,” Owl said. “I lost a game of backgammon this morning.”

Hand-cranked radios bring news. Owl has hooked up speakers to his iPod to play the Beatles.

Rain has drenched his “Collected Works of Robinson Jeffers,” but Owl hopes to do some reading.

Across the street, at the Physical Sciences Building, professors grow increasingly angry. One has posted a huge sign across his windows reading: “Protesters Go Home.”

“A piece of concrete was thrown through my lab’s window,” said Biochemistry Professor Glenn Millhauser, who conducts research on human proteins. “Human waste was spewed around one restroom. It was a huge mess.”

The Physical Sciences Building was vandalized during a December rally. The vandals pulled fire alarms and defaced walls with graffiti.

Hired security guards now screen all visitors. “Here we are in a system that is starved for funding – and we’re spending all this money on security,” Millhauser said.

Campus expansion is critical to the educational needs of the state’s growing population – particularly in the popular Health Sciences major, said Donald Smith, a professor of environmental toxicology, who studies the ill effects of lead, arsenic and other metals on human health.

“We’re maxed out on space,” he said. “We’re very sensitive to the need to grow carefully.

“It’s elitist. Why was it OK for them to come, but not the generation that follows?” asked Millhauser. “‘The kids working here in the labs, doing medical research – that, for me, defines commitment.”

The university will go to court Feb. 21 to ask for an order to get the sitters out of the trees, arguing that the protest constitutes illegal camping and has created dangerous, unsanitary conditions.

But extricating the unwilling could pose its own problem. If pulled, they could fall and get hurt.

Lisa M. Krieger is a science writer at The Mercury News, covering research, scientific policy and environmental news from Stanford University, the University of California, NASA-Ames, U.S. Geological Survey and other Bay Area-based research facilities. Lisa also contributes to the Videography team. She graduated from Duke University with a degree in biology. Outside of work, she enjoys photography, backpacking, swimming and bird-watching.

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